Effective early termination algorithm for depth map intra coding in 3D-HEVC

In the current high-efficiency video coding-based three-dimensional video coding (3D-HEVC) design, new depth intra modes including depth modelling modes and region boundary chain coding are applied for depth map coding. These partition-based intra modes achieve the highest possible coding efficiency, but result in extremely large encoding time which obstructs the 3D-HEVC from practical applications. An efficient early termination algorithm for depth map coding in 3D-HEVC is proposed. It makes use of the coding information from the spatial neighbouring depth map treeblock and the co-located texture video treeblock to predict the depth map intra mode treeblock and terminate its mode decision process early. Experimental results show that the proposed algorithm can achieve an average computational saving of about 40% with negligible loss of rate distortion performance in the 3D-HEVC encoder.